In December, St. Louis typically sees daytime highs of 6.4°C and overnight lows around -3.0°C. Compared to the annual average high of 19.0°C, December runs -12.6°C.
December in St. Louis averages a daytime high of 6.4°C and an overnight low of -3.0°C.
December runs -12.6°C compared to St. Louis's annual average high of 19.0°C, ranking #11 of 12 months by warmth.
Plan for daytime highs near 6.4°C and cooler evenings around -3.0°C.